The present invention relates to a power driven soil working apparatus and is more particularly concerned with means for performing a plant uprooting operation prior to a mechanical harvesting operation.
It has been demonstrated to be practical to sever and uproot various row crops, such as tomatoes, to allow a degree of wilting of the plants prior to a mechanical harvesting operation. Also, working of the soil prior to harvesting can help to dry a wet field sufficient to permit an otherwise impractical harvesting operation.
Certain of the prior art harvesters for tomatoes, cucumbers, potatoes, onions and the like have included sickle bars, stationary shear knives, rotating horizontal discs and the like, operable for cutting plants before fruit harvesting.
Moreover, harvesters disclosed in U.S. patents to Malley et al, U.S. Pat. No. 3,690,383, issued Sept. 12, 1972, and Roberts, U.S. Pat. No. 2,954,085, issued Sept. 27, 1960, both include a pair of horizontally oriented rotating bars, one positioned for operation below the surface of the soil for severing crop roots, and the other being vertically and horizontally spaced from the first in a trailing relationship for operation above the soil surface to elevate the severed plants. The rotating bars disclosed in each of these patents require a substantial spacing in order to perform the desired severing and elevating operations.
The prior art discs and sickle bar units require considerable horsepower and the wear problems are substantial. The stationary cutting knives will not work satisfactorily in excessively weedy conditions or with certain soil conditions, such as high moisture. Rotating bars disclosed in the prior art, though successful in many respects, will not work properly in weeds and heavy foliage due to considerable wrapping of foliage around the individual bars to a point where machine down time is required to clean the bars.
The plural bar system of the present invention represents improvement in the art in that the problems referred to above are overcome thereby. In fact, the plural bar system of the present invention operates efficiently on a continuous basis at high harvesting speeds.